/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grids Lab or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
package cgl.narada.wsinfra.deployment;

import java.util.Hashtable;

import cgl.narada.wsinfra.deployment.impl.FilterPipelineImpl;
import cgl.narada.wsinfra.exception.DeploymentException;

/** This class provides a Factory for creating filter pipelines. Filter 
    pipelines need to have valid identifiers.

    @author Shrideep Pallickara
    $Date: 2005/07/29 22:41:29 $
    $Revision: 1.4 $
*/


public class FilterPipelineFactory {

  public static final FilterPipelineFactory instance = 
  new FilterPipelineFactory();
  private Hashtable pipelines;
  private String moduleName = "FilterPipelineFactory: ";


  private FilterPipelineFactory() {
    pipelines = new Hashtable();
  }

  public static FilterPipelineFactory getInstance() {
    return instance;
  }

  public FilterPipeline newFilterPipeline(String identifier)
    throws DeploymentException {

    checkForProblemsWithIdentifier(identifier);
    
    if (pipelines.containsKey(identifier) ) {
      String errorReport = moduleName + "A pipeline with the identifier [" +
	identifier + "] already exists within the filter pipeline factory.";
      throw new DeploymentException(errorReport);
    }

    FilterPipeline filterPipeline = new FilterPipelineImpl();
    filterPipeline.setIdentifier(identifier);
    pipelines.put(identifier, filterPipeline);

    return filterPipeline;
  }

  /** Creates an instance of the Filter Pipeline. */
  public FilterPipeline getFilterPipeline(String identifier)
    throws DeploymentException {
    checkForProblemsWithIdentifier(identifier);
    if (!pipelines.containsKey(identifier) ) {
      String errorReport = moduleName + "A pipeline with the identifier [" +
	identifier + "] DOES NOT exist within the filter pipeline factory.";
      throw new DeploymentException(errorReport);
    }
    FilterPipeline filterPipeline = (FilterPipeline)pipelines.get(identifier);
    
    return filterPipeline;
  }

  /** Dispose off a filter pipeline. */
  public boolean disposeFilterPipeline(FilterPipeline filterPipeline)
    throws DeploymentException {
    if (filterPipeline == null) {
      throw new DeploymentException(moduleName + 
				    "Specified FilterPipeline is NULL.");
    }
    String identifier = filterPipeline.getIdentifier();
    
    checkForProblemsWithIdentifier(identifier);
    pipelines.remove(identifier);
    return true;
  }


  private void checkForProblemsWithIdentifier(String identifier) 
    throws DeploymentException {

    if (identifier == null) {
      throw new DeploymentException("The specified identifier for the " +
				    "FilterPipeline is NULL. ");
    }

  }



}





